Django-conditions

- Add support for Django 3.2
- Add support for Python 3.9-3.10
- Drop support for Python 3.6
- Switch CI from Travis to Github Actions
- Rename default branch from `master` -> `main`

- Run autoformatters provided by opstrich including pyupgrade, isort, and black
- Publish package to PyPi using opstrich task
- Drop support for Python 3.5

- Add `long_description_content_type` as Markdown in `setup.py`, correcting an issue where the package description failed to render correctly on PyPI

Note: PyPI now requires package descriptions to render. Therefore [v0.9.16](https://github.com/RevolutionTech/django-conditions/releases/tag/v0.9.16) could never be published to PyPI.

- Fix issue preventing conditions widget from rendering in Django 2.1+
- Add support for Django 3.0-3.1
- Add support for Python 3.8
- Drop support for Django 1.11-2.1
- Drop support for Python 2.7, 3.4

- Require `django-jsonfield` >= 1.1.0
- Add support for Django 2.1-2.2
- Add support for Python 3.7
- Drop support for Django 1.8-1.10

- FIX: Prevent users from pasting in whitespace into condition key and operand freetext

Note: [v0.9.14](https://github.com/RevolutionTech/django-conditions/releases/tag/v0.9.14) was a bad tag because it did not include the version bump in `setup.py`.